UK light-heavyweight Buatsi earned a win yet underwhelming beginning to life under recent management with a points victory over Zach Parker in Manchester.
The Olympic bronze medallist's activity level likely gained him a judges' verdict in a competitive 10-round fight at the boxing arena.
But the challenger found success, connecting with powerful individual punches in a contest where the styles didn't complement each other, with constant grabbing marring the fight.
The officials had it 96-94 in favor to Buatsi, with the third a 95-95 draw.
"It wasn't my finest showing but what defines champions? They win," the victor stated in the ringside as he was faced boos from the crowd.
The Londoner returned to winning ways after his initial pro loss - an thrilling contest with his previous opponent in last winter - to claim a twentieth professional win.
Some ringside observers believed the challenger, thirty-one, should have been awarded the decision but the Derbyshire fighter experienced the second defeat of his 28-match career.
Buatsi Secures Victory in Slow Affair
The fighter's advancement has stalled in the past few years through management issues and extended periods of lack of fights.
Earlier forecast as the next star of UK boxing, he now is positioned trying to achieve expectations - possibly in what feels like a ultimate opportunity - under new promotional backing.
He started carefully, with neither fighter ready to be aggressive in a tentative initial rounds.
Parker, whose only previous defeat came at the lower weight class against John Ryder in 2022 after damaging his hand mid-fight, was participating in his second bout at light heavyweight.
By the fight's midpoint, the underdog had stayed in contention, causing problems for the favorite, who worked behind a protective stance to narrowly win the more effective stanzas.
The crowd's patience wore thin amid regular grabbing, with the challenger going down various instances during clinches.
Parker finished the stronger, but several stanzas were difficult to score. Nevertheless, ex-champion Carl Frampton - providing analysis for the broadcast network - had it significantly in favor for the challenger, scoring for Buatsi just a single round.
Buatsi progresses, but with the caliber of hard hitter Benavidez, and Russian star Bivol leading the category, the path to championship success - based on this performance - still looks steep.
Ricky Hatton Tribute Fuels Manchester Derby Fight
In the secondary fight, Lyndon Arthur defeated Bradley Rea by divided decision in a excellent local rivalry battle to secure the European light heavyweight belt.
The venue became quiet for a deeply poignant tribute prior to the bout as 10 bells sounded in honor of local hero Hatton, who died at age 46 in September.
It was the initial significant broadcast fight night in the location since Hatton's death. As the final chime ended, the stillness transitioned to a shout of "there's only one Ricky Hatton".
The competition inside the ropes equaled the emotion. The eventual winner was sent to the canvas by a powerful punch directly to the chin in the early round, standing uncertainly to his footing on the eight count.
But the traditional red shorts of the fighter soon advanced again. On the opposite side, the opponent - in competitive blue - was damaged early, noticeable damage forming under his orbital area as the pair traded powerful shots.
The challenger, 27, landed power punches but Arthur, thirty-four, responded in kind with effective uppercuts as the pace hardly diminished over twelve rounds.
The victor narrowly won the result with judges scorecards of even score, close margin and wider gap, but the two athletes were determined and full of heart, everything their inspiration the legend stood for.
